Positioning system for detecting position of cleansing device

Abstract

A positioning system for detecting the position of a cleansing device is provided. The positioning system includes a cleansing device and a base station. The cleansing device includes a controlling unit, a cleaning module, a first emitting unit, and a second emitting unit. The controlling unit controls cleansing operation performed on a cleansing region taken care by the cleaning module, controls the first emitting unit to emit an initial signal, and controls the second emitting unit to emit an ultrasonic signal. The base station includes a first receiving unit, two second receiving units, and a computing unit. The first receiving unit receives the initial signal. The second receiving units receive the ultrasonic signal. The computing unit computes the position of the cleansing device according to the initial signal received and the point in time when the ultrasonic signal is received.

What is claimed is: 
     
         1 . A positioning system for detecting a position of a cleansing device, the positioning system comprising:
 a cleansing device comprising a body, a controlling unit, a cleaning module, a first emitting unit, and a second emitting unit, the controlling unit is being connected to the cleaning module, the first emitting unit, and the second emitting unit, controlling a cleansing operation performed on a cleansing region taken care by the cleaning module, controlling the first emitting unit to emit an initial signal, and controlling the second emitting unit to emit an ultrasonic signal, the ultrasonic signal being transmitted at a transmission speed, wherein the controlling unit, the cleaning module, the first emitting unit, and the second emitting unit are disposed on the body; and   a base station comprising a first receiving unit, two second receiving units, and a computing unit, the first receiving unit being connected to the computing unit and receiving the initial signal, the two second receiving units being connected to the computing unit for receiving the ultrasonic signal and being separated by a constant distance, and the computing unit computing the position of the cleansing device according to the initial signal received by the first receiving unit and a point in time when the ultrasonic signal is received by each of the second receiving units.   
     
     
         2 . The positioning system of  claim 1 , wherein the controlling unit controls the first emitting unit to emit the initial signal and controls the second emitting unit to emit the ultrasonic signal simultaneously, and the computing unit executes a computation procedure comprising the steps of:
 creating a standard point in time according to a point in time when the first receiving unit receives the initial signal;   creating a first point in time according to a point in time when one of the two second receiving units receives the ultrasonic signal, and creating a second point in time according to a point in time when the other one of the two second receiving units receives the ultrasonic signal;   computing a first time interval equal to a time difference between the first point in time and the standard point in time, and computing a second time interval equal to a time difference between the second point in time and the standard point in time;   computing a first distance equal to a product of the first time interval and a transmission speed of the ultrasonic signal so as to calculate a distance between one of the second receiving units and the cleansing device, and computing a second distance equal to a product of the second time interval and the transmission speed of the ultrasonic signal so as to calculate a distance between the other one of the second receiving units and the cleansing device; and   computing a position of the cleansing device relative to the base station according to the constant distance, the first distance and the second distance three relation.   
     
     
         3 . The positioning system of  claim 2 , wherein a same delay time of the controlling unit and the computing unit is configured, the delay time being equal to a time interval between a point in time when the first emitting unit emits the initial signal and a point in time when the second emitting unit emits the ultrasonic signal, wherein the delay time is included in the first and second time intervals, wherein the step of computing the first time interval and the second time interval in the computation procedure executed by the computing unit further comprises deducting the delay time between the first point in time and the standard point in time and deducting the delay time between the second point in time and the standard point in time. 
     
     
         4 . The positioning system of  claim 2 , wherein the base station further comprises a storing module connected to the computing unit and adapted to store every position of the cleansing device moving relative to the base station. 
     
     
         5 . The positioning system of  claim 1 , wherein the first emitting unit is an infrared receiver, and the first receiving unit is an infrared receiver. 
     
     
         6 . The positioning system of  claim 1 , wherein the first emitting unit is a radio frequency transmitter, and the first receiving unit is a radio frequency receiver.